3 ms·

It will overflow to filler[3]. ie the 4th byte. see the struct sockaddr: * first 2 bytes: Address Family, * next 2 bytes: port, * next 2 bytes: ipaddr,

• greenyoda 12y ago
  "It will overflow to filler[3]" Not with any correct C compiler, it wont. Here's a simple test program I ran on Linux: #include <stdio.h> int main() { char filler[16] = {0}; int i; unsigned short s1 = 0xFFFF; unsigned long l1 = 0xFFFFFFFF; filler[0] = (unsigned short)s1; filler[2] = (unsigned short)s1; filler[4] = (unsigned long)l1; for (i = 0; i < 8; i++) printf("filler[%d] = %d\n", i, filler[i]); } And when you run it, all the elements of filler that haven't been explicitly assigned to are still 0, even though the unsigned shorts and longs that were assigned to them have '1' in all their bits: $ gcc filler.c $ ./a.out filler[0] = -1 filler[1] = 0 filler[2] = -1 filler[3] = 0 filler[4] = -1 filler[5] = 0 filler[6] = 0 filler[7] = 0 Since htons() swaps the bytes in its result, you should just be able to assign the value it returns directly: struct sockaddr_in serv_addr; ... serv_addr.sin_port = htons(port); (See, for example: https://en.wikibooks.org/wiki/C_Programming/Networking_in_UNIX https://en.wikibooks.org/wiki/C_Programming/Networking_in_UN...)